Bowl releasing slip



July 13, 1937. A. s. VOLPIN IBOWL'RELEASING SLIP 2 Sheets-Sheet 1 W M MM 4 Filed March 4, '1935 July 13, 1937. a VOLHN I 2,086,652

BOWL RELEASING SLIP Filed March 4, 1935 2 Sheets-Sheet 2 Patented July 13, 1937 STATE BOWL RELEASING: sur 7 Alexander s. Volpin, Houstonl Tex. Application March 4, 1935'; 9,263 l 12 Claims; (CLZ4-2t3) The invention relates to slips for supporting pipe in oilwell drilling and producing operations. It is necessary in handlingYpipe. while his being introduced. into and withdrawn from deep well'sin oil .well operations to support the pipe at the upper. end of the well either within a tapered bowl in the casing head orin the platform of the rotary which is. employed to rotate the pipeQ' Slips of this general character are well known in the art. ltwis an object of the invention to provide a slipiforJshppOttihg pipe in a tapered seat which is"coristructe';d sothat it will easily release when the pipe" is ur 'wn' upwardly relative tothesuptort. a V.

"iljdesi-re to; provide a releasing surface on the outer'di'a'meter ofjthe slip-which willengage the tapered bowl-Yin supporting the pipe, .but which will easily release w'hen the pipe is elevated. I another object of my invention to form thelbbwl-Iengag-ing portionof the slipso that, its outer, diameter? will 'be-.,r.educed,, as{.the. .slipis mbreau warmy duringthe releasing operation. It ;is also ,an ,object to provide a flexible releasi 'g"'iii'face for'theouter portions, or the slip which isvsdmountedl relative to the body of the slip that' it'furnishes a substantial support for th pipe. I I f urther idesire, to provide a removable pipeengaging; portion forthe "slip which will be reoyablearid' renewable and will form a, frictional engagement with the'pipe oiv comparatively large area. i v a, j j 'iIIt. as further object of the invention to make up abbwl-erigaging structure for the slip-s which hasasubstantial area of engagement with the seat b'owl and will .not be easily broken or worn I drawings herewith; Fig. 1 s,a"tdppla'fr 1 view of abushingor, adapter for ,on 'rotaities and showing the use of slips of ""improvediform. I v "i l igjz i's ajcentral vertical section through the slipandbushi'ng! ..Eig.-3, is a side in'g theinvention. V v

'g. j4"is"a front elevation of a slipjaw on my invention'is employed. 5"is atransverse section on elevation of a slip incorporat' the plane 5- 5 F g. .6 szan enlarged detail of adiagrammatic atur fsh'owingthe way in which the releasing atesngagelthe bowl of thebushing. I

have shown'the slip as being supported in a ed. seat lj'upon ,a polygonal bushing 'or is mqved pwa s ada ter: 2 to be seated, within aseat in platform, used in a rotary drilling operations. This is sir nplyillustrative, it being'cornmon to provide a tapered seat, such as |',.fi"or supporting slips of tlfiischalaclierf v I v The slips are'twoinlnumbeneach of the slips upper .endsjby, a transverse bolt 5 3 connected together at their extending troughieyjelts 5 upon eachfofthe jaws, said boltsactingiasac .iT ws 2 the u ua onnectiongf or a handlefi. downwardly'tape red contour being wedge-shaped in transverse sec non, the miter.v wardly and the surface? being tapered down inner, f ace being substantially vertical tofengage 'thejpi'p'e l. Each set of two jaws is ,cdnnectedat the upper end by the handle as ,shownandjsaidpiaws are further, connected by through. bolts, .8 shown in Fig. 3. To accommo-f date,these;bolts the e -jeiiati i te ding wal outer faces-of the jaws 3 are 9.,. providing an outwardly 1ex- 1 I ll, v which is formed with openings allowthejpassa'ge of the bolts 8 one bolt be ing towardthe, upper end of theja'wj and the other interi ediate the'enjds'thereoi. These bolts "'t "rough" the openin i it als so tha the aws play pr'rnovernent;

' Each of I the two gs indicated at i l 1: hav a at v 'aws 'is' equipped with alow'er plateffllZ arcuatedn shape, fitting against the lowerfen O ,1'ie jaws and heldin position" by set screws 13 ea; upward from the plate into the jaw-T v The construction of'thebowl-engaging surface of. the lipis 'one joi the principal features of haven-2 in" the invention "To form this. outer howl-engaging surface I recess the outer curved face of the jaw with a dove-tailed mortise shown in Fig; 5. This mortise extends short of the upper endandvthe downwardly inclined shoulder runs the upper wall of the recess.

The lower end fthe rnortised recess is open except for the closure plate 'I 2 previously noted.

' Within thisj'n ortis'ed (recess Ifli'iave placed a series of superposed flattenedplates l6, which are downwardly inclined in cess; as shown best in the 11 1 61 {plate has a firm inclined shoulder their position in the re- Fig. '2. iThe, upper face of I "Support against the 15 of the mortise. Said plates are introduced upwardly from the lower endinto position in the mortise and the lowermost plate is held i w 4 I "Epositionresilientlyby'a l1 or other resilient'material. I contemplate holding the platesgenerally in Contact with each 'otherbyfso supporting them that when the slip ythe plates L na'y be pivoted at pad of rubber their inner ends to swing downwardly at their outer ends, thus permitting ready release.

The forward vertical face of each jaw is provided with a removable pipe-engaging surface. This is provided upon the plate l8, which, as seen in Fig. 5, is set within a recess or groove I9 formed in the forward face of the jaw. The pipe-engaging portion of the plate is arcuate at 20 and toothed to form a frictional face to engage with the pipe and frictionally support the'same. These plates are introduced into the recess at the upper end, the plate resting at its lower end upon a shoulder 2| in the groove or recess. The plates are further held in position by set screws 22 inserted from the forward side into the body of the jaw.

For the effective operation of releasing the slipfrom the bowl, the plates l6, which form the releasing surface, are rounded at the upper and lower edges on the side of the plate directed toward the inner wall of the seat or mortise in the slip. Thus with reference to Fig. 6 it will be seen that the upper edge at 23 is rounded and the lower inclined edge is rounded at 24 and the lower portion of the inner face of the plate is also somewhat curved as shown at 25.

In the operation of the slip it will be understood that when the pipe I is supported within the tapered seat by means of the slip member the weight of the pipe will exert a strong downward pull upon the slips, wedging them into the seat and forcing them strongly into frictional engagement with the pipe. In deep well drilling, the weight of the drill stem may exert many tons of downward pull upon the slips. The result is that the slips tend to wedge tightly between the tapered seat and the pipe. When the pipe is thereafter to be released the pipe 1 is pulled upwardly by the draw works and cable connected therewith and the slips then tend to move upwardly with the pipe and release from the bowl so that the slips may be removed from their position, allowing the further handling of the pipe.

In order that the slips do not wedge and fail to release when the pipe is drawn upwardly, my plates l6, which form the contacting surface with the bowl, are arranged to have a rocking motion on the outer surface of the slip which tends to easily release from the bowl. This will be understood from Fig. 6. The inner surface of the mortise M in the slip is indicated at M in Fig. 6. The body of the slip including this inner wall l4 tends to move upwardly with the pipe. As it moves upwardly the plates l6 are moved upwardly at their inner ends first, and the plates will rock somewhat, moving downwardly on their outer surfaces 26 into the dotted line position there indicated. It will be seen, therefore, that the effective outer diameter of the slip has been decreased, thus allowing the slip to move freely in an upward direction out of the seat I of the bowl. The rounded edges upon the plate l6 enable this rocking motion without difficulty and contribute to the release of the slips.

It will thus be seen that my improved slip releases first at the outer diameter. This is of some importance in that there is a longer lever arm between the pipe which moves upwardly and the releasing surface than would be the case if the releasing surface were at the pipe. Furthermore, this reduction in the diameter of the slip, due to the rocking motionv of the plates in their recesses, also enables the slip to release more easily. On the other hand, where the weight of the pipe is supported upon the slip it will be seen that the tendency will be for the outer edges of the plates I6 to move upwardly. They are prevented from this movement by contact with each other and with the upper shoulder I5 of the recess. The tendency to rock upwardly, however, tends to force the slip inward toward the pipe and increase the frictional engagement with the pipe, thus obtaining a firm hold thereon, which will not allow the pipe to drop. The further advantages of this device will be obvious to those skilled in the art.

What I claim as new is: i I

l. A pipe-engaging slip including a plurality of jaws the outer surfaces of which are tapered downwardly to engage within a downwardly tapered slip bowl, an inner pipe-engaging face on each jaw, there being a mortised recess on the outer tapered surface of each of said jaws, said recess having an upper shoulder, superposed plates in said recess, and means to yieldably hold said plates upwardly toward said shoulder.

2. A pipe engaging slip including a plurality of jaws the outer surfaces of which are tapered downwardly to engage within a downwardly ta-.

pered slip bowl, an inner pipe engaging face on each jaw, there being a mortised recess on the outer tapered surface of each of said jaws, said recess having an upper downwardly'and outwardly tapered shoulder, superposed plates in said recess, and means to yieldably hold said plates upwardly toward said shoulder.

3. A pipe-engaging slip including a plurality of jaws, means to handle said jaws as a unit, an inner pipe-engaging face on each jaw, an outer arcuate surface on each jaw tapered to engage a downwardly tapered slip bowl, said outersurface including the outer edges of a plurality of superposed plates supported by each of said jaws in a downwardly and outwardly inclined position and a support for said plates yieldable to permit said plates to incline still further in a downward direction at their outer margins when the body of said slip is moved upwardly out of bowl-engaging position.

4. A pipe engaging slip including a plurality of jaws, an inner pipe engaging face on each jaw, an outer arcuate surface on each jaw tapered to engage a downwardly tapered slip bowl, said outer surface including the outer edges of a plurality of superposed plates supported by each of said jaws in a downwardly and outwardly inclined position, means to hold said plates resiliently in said inclined position but adapted to yield to allow said plates to move relatively downward adjacent said bowl to release from bowl-engaging position.

5. A pipe-engaging slip including a plurality of jaws, an inner pipe engaging face on each jaw, an outer arcuate surface on each jaw tapered to engage a downwardly tapered slip bowl, said outer surface including the outer edges of a plurality of superposed plates mounted in a mortised recess in said jaw, an upper shoulder for said recess and means to hold said plates resiliently against said shoulder.

6. A pipe engaging slip including a plurality of jaws, means to handle said jaws as a unit, an inner pipe engaging face on each jaw, an outer arcuate surface on each jaw tapered to-engage a downwardly tapered slip bowl, said outer surface including the outer edges of a plurality of superposed plates mounted in a mortised recess in said jaw, an upper shoulder for said recess and means to hold said plates resiliently against said shoulder, the inner edges of said plates having rounded corners to permit rocking of said plates and allow the bowl-engaging edge of each plate to move relatively downward during release from said bowl.

7. In a pipe engaging slip, an arcuate jaw ta- 5 pered downwardly on its outer face to engage a tapered slip bowl, a longitudinal recess in the outer tapered surface of said jaw having an upper shoulder, a plurality of superposed plates in each recess, a pad of rubber below said plates in said recess, means to close the lower end of said recess, and a pipe-engaging inner face on said jaw.

8. In a pipe-engaging slip, an arcuate jaw tapered downwardly on its outer face to engage a. tapered slip bowl, a longitudinal recess in the outer face of said jaw having an upper shoulder, a plurality of superposed plates in each recess, a pad of rubber below said plates in said recess, means to close the lower end of said recess, a pipeengaging inner face on said jaw, said plates having their inner edges rounded to allow said plates to rock relative'to the inner side of said recess.

9. In a pipe-engaging slip, an arcuate jaw tapered downwardly on its outer face to engage a 'tapered slip bowl, a longitudinal recess in said jaw having an upper shoulder, a plurality of said plates yieldable to permit said plates to rock and incline downwardly at their outer margins to reduce the outer diameter of said slip.

10. A pipe-engaging slip, a jaw, means on its inner surface adapted to engage a pipe, said slip being formed to engage within a downwardly tapered slip bowl, and releasable means on each jaw to contact with said slip-bowl, comprising a 5 series of superposed plates, resiliently supported so that the outer edges of said plates may rock downwardly to decrease the outer dimension thereof when said slip is moved relatively upward.

11. The combination of a slip bowl and a slip 10 therein, a tapered surface in said bowl to receive the load of said slip, and movable means on the outer surface of the slip to contact said tapered surface, said means being movable downwardly relative to said slip so as to vary the diameter 15 of the slip as the load is removed therefrom and the slip is raised upwardly.

12. In a pipe engaging slip, a jaw, a pipe engaging surface on the inner side thereof, the outer portion of said jaw being downwardly tapered, 20 flexible means associated with the outer face of each jaw to engage with a downwardly tapered slip bowl, said means including plates yieldable downwardly to decrease the outer diameter of said slip as said slip is moved relatively upward. 25

ALEXANDER S. VOLPIN. 

